... We describe a methodology for the synthesis of extended aromatic structures through dehydrative C–C coupling from readily accessible diols. Treatment of the diols with a Brønsted acid (para-toluenesulfonic acid) induces the nucleophilic addition of an arene or heteroarene, yielding fully aromatic products in high to quantitative yields with thiophenes, furan, indole, and N,N-dimethylaniline as cou ...

... Epoxide-opening ether cyclizations are shown to occur on π-acidic aromatic surfaces without the need of additional activating groups and with autocatalytic amplification. Increasing activity with the intrinsic π acidity of benzenes, naphthalenediimides (NDIs) and perylenediimides (PDIs) support that anion−π interactions account for function. Rate enhancements maximize at 270 for anion−π catalysis ...

... A hybrid of high level and low level quantum mechanics (QM) methods has been employed to predict intrinsic and apparent energy barriers for the direct proton exchange mechanism of methane, ethane, propane, n-butane, and i-butane on Brønsted sites of H-MFI. The specific hybrid MP2:PBE+D2 + ΔCC implementation used is known to yield the so-called “chemical accuracy” (±4 kJ/mol). Whereas the apparent ...

... Particulate methane monooxygenase (pMMO) is an enzyme that oxidizes methane to methanol with high activity and selectivity. Limited success has been achieved in incorporating biologically relevant ligands for the formation of such active site in a synthetic system. Here, we report the design and synthesis of metal–organic framework (MOF) catalysts inspired by pMMO for selective methane oxidation t ...

... Hybrid assemblies composed of phospholipids and amphiphilic polymers have been investigated previously as a biomimetic model of biological cells. However, these studies focused on the functions of polymers in a sea of membrane lipids. Here, we prepared a highly stable peptide-lipid hybrid vesicle from a combination of an amphiphilic polypeptide and the phospholipid, 1,2-dimyristoyl-sn-glycero-3-ph ...

... The biosynthetic route to the napyradiomycin family of bacterial meroterpenoids has been fully described 32 years following their original isolation and 11 years after their gene cluster discovery. The antimicrobial and cytotoxic natural products napyradiomycins A1 and B1 are produced using three organic substrates (1,3,6,8-tetrahydroxynaphthalene, dimethylallyl pyrophosphate, and geranyl pyrophos ...

... sn2-15-Hydroperoxy-eicasotetraenoyl-phosphatidylethanolamines (sn2-15-HpETE-PE) generated by mammalian 15-lipoxygenase/phosphatidylethanolamine binding protein-1 (15-LO/PEBP1) complex is a death signal in a recently identified type of programmed cell demise, ferroptosis. How the enzymatic complex selects sn2-ETE-PE as the substrate among 1 of ∼100 total oxidizable membrane PUFA phospholipids is a ...

... Microstructured metal–organic framework (MOF) glasses have been produced by combining two amorphous MOFs. However, the electronic structure of these materials has not been interrogated at the length scales of the chemical domains formed in these glasses. Here, we report a subwavelength spatially resolved physicochemical analysis of the electronic states at visible and UV energies in a blend of two ...

... Using a phenoxazine-based organic photosensitizer and an iron porphyrin molecular catalyst, we demonstrated photochemical reduction of CO₂ to CO and CH₄ with turnover numbers (TONs) of 149 and 29, respectively, under visible-light irradiation (λ > 435 nm) with a tertiary amine as sacrificial electron donor. This work is the first example of a molecular system using an earth-abundant metal catalyst ...

... The ligand [2,2′-bipyridin]-6(1H)-one (bipy-6-OH) has a strong accelerating effect on the Pd-catalyzed direct arylation of pyridine or arenes. The isolation of relevant intermediates and the study of their decomposition unequivocally show that the deprotonated coordinated ligand acts as a base and assists the cleavage of the C–H bond. Mechanistic work indicates that the direct arylation of pyridin ...

... Enantioenriched 2-aryl azepanes and 2-arylbenzazepines were generated biocatalytically by asymmetric reductive amination using imine reductases or by deracemization using monoamine oxidases. The amines were converted to the corresponding N′-aryl ureas, which rearranged on treatment with base with stereospecific transfer of the aryl substituent to the 2-position of the heterocycle via a configurati ...

... The blooming field of structural DNA nanotechnology harnessing the material properties of nucleic acids has attracted widespread interest. The exploitation of the precise and programmable Watson–Crick base pairing of DNA or RNA has led to the development of exquisite nucleic acid nanostructures from one to three dimensions. The advances of computer-aided tools facilitate automated design of DNA na ...

... Alboflavusins (AFNs) are a group of cyclohexapeptides with moderate antibacterial and antitumor activities from Streptomyces alboflavus sp. 313. In vivo and in vitro studies proposed that AFNs are biosynthesized by a nonribosomal peptide synthetase machinery, and the 6-Cl-L-Trp precursor is supplied by a tryptophan halogenase gene located outside the afn gene cluster. Guided by the structure–activ ...

... Dielectric screening plays an important role in reducing the strength of carrier scattering and trapping by point defects for many semiconductors such as the halide perovskite solar materials. However, it was rarely considered as a screen to find new electronic semiconductors. We performed a material search study using the dielectric properties as a screen to identify potential electronic material ...

... The arginine/glycine-rich region termed the RGG domain is usually found in G-quadruplex (G4)-binding proteins and is important in G4–protein interactions. Studies on the binding mechanism of RGG domains found that small segments (RGG motif) inside the domain contribute greatly to the G4 binding affinity. However, unlike the entire RGG domains that have been broadly explored, the role of the RGG mo ...

... The preparation of membranes with high selectivity based on specific chemical properties such as size and charge would impact the efficiency of the world’s energy supply, the production of clean water, and many other separation technologies. We report a flexible synthetic protocol for preparing highly ordered two-dimensional nanoporous polymeric materials (termed covalent organic frameworks or COF ...

... The stereochemistry of chiral-at-metal complexes is much more abundant, albeit complicated, than chiral-at-carbon compounds, but how to make use of stereolabile metal-centers remains a formidable challenge due to the highly versatile coordination geometry of metal ions and racemization/epimerization problem. We demonstrate herein a stepwise assembly of configurationally stable [Pd₆(FeL₃)₈]²⁸⁺ (Δ/Λ ...

... The introduction of B ← N coordinate bond—isoelectronic to C–C single bond—into π-systems represents a promising strategy to impart exotic redox and electrochromic properties into conjugated organic molecules and macromolecules. To achieve both reductive and oxidative activities using this strategy, a cruciform ladder-type molecular constitution was designed to accommodate oxidation-active, reduct ...

... Enzyme engineering tends to focus on the design of active sites for the chemical steps, while the physical steps of the catalytic cycle are often overlooked. Tight binding of a substrate in an active site is beneficial for the chemical steps, whereas good accessibility benefits substrate binding and product release. Many enzymes control the accessibility of their active sites by molecular gates. H ...

... We report synthesis and characterization of near-infrared (NIR)-absorbing/emitting Thiele’s hydrocarbon derivatives, in which four aryl groups are bridged to a quinodimethane skeleton. The quinoid structure of the bridged-tetra-aryl-p-quinodimethanes (BTAQs) was confirmed by spectroscopic, X-ray crystallographic, and computational methods. Although quinodimethane derivatives with a small HOMO–LUMO ...

... The widespread deployment of carbon capture and sequestration as a climate change mitigation strategy could be facilitated by the development of more energy-efficient adsorbents. Diamine-appended metal–organic frameworks of the type diamine–M₂(dobpdc) (M = Mg, Mn, Fe, Co, Ni, Zn; dobpdc⁴– = 4,4′-dioxidobiphenyl-3,3′-dicarboxylate) have shown promise for carbon-capture applications, although questi ...

... Sodium batteries have been regarded as promising candidates for large-scale energy storage application, provided cathode hosts with high energy density and long cycle life can be found. Herein, we report NASICON-structured Na₃MnZr(PO₄)₃ as a cathode for sodium batteries that exhibits an electrochemical performance superior to those of other manganese phosphate cathodes reported in the literature. ...

... Singlet fission (SF) is a spin-allowed process in which a singlet exciton, ¹(S₁S₀), within an assembly of two or more chromophores spontaneously down-converts into two triplet excitons via a multiexciton correlated triplet pair state, ¹(T₁T₁). To elucidate the involvement of charge transfer (CT) states and vibronic coupling in SF, we performed 2D electronic spectroscopy (2DES) on dilute solutions ...

... Providing a mechanically stable and electronically efficient coupling between a molecule and an electrode is critical to the study of charge transfer and conductance of the molecule. A common method is to link the molecule to Au electrodes via a linker (e.g., thiol terminal of the molecule). Here we study the mechanical stability and electronic coupling of a S–Au bond in single-molecule junctions ...

... We present the synthesis and characterization of the K⁺-intercalated rubrene (C₄₂H₂₈) phase, K₂Rubrene (K₂R), and identify the coexistence of amorphous and crystalline materials in samples where the crystalline component is phase-pure. We suggest this is characteristic of many intercalated alkali metal–polyaromatic hydrocarbon (PAH) systems, including those for which superconductivity has been cla ...

... Small-molecule detection is important for many applications including clinical diagnostics, drug discovery, and measurements of environmental samples and agricultural products. Current techniques for small-molecule detection suffer from various limitations including low analytical sensitivity and complex sample processing. Furthermore, as a result of their small size, small molecules are difficult ...

... The conductive framework is generating considerable interest for lithium metal anodes to accommodate Li⁺ deposition, due to its ability to reduce electrode current density by increasing the deposition area. However, in most cases, the electroactive surface area is not fully utilized for the nucleation of Li in 3D current collectors, especially under high current densities. Herein, uniform nucleati ...

... Neurite outgrowth is the critical step of nervous development. Molecular probes against neurites are essential for evaluation of the nervous system development, compound neurotoxicity, and drug efficacy on nerve regeneration. To obtain a neurite probe, we developed a neurite-SELEX strategy and generated a DNA aptamer, yly12, that strongly binds neurites. The molecular target of yly12 was identifie ...

... Quantum mechanical computations and molecular dynamics simulations have been used to elucidate the factors that control reaction outcomes in ambimodal transition states leading to both dipolar and Diels–Alder cycloaddition products, which can interconvert via α-ketol rearrangements. The dipolar cycloaddition pathways were found to be disadvantaged due to the persistence of charge separation after ...

... Materials having a high dielectric constant are needed for a variety of electrical applications from transistors to capacitors. Ferroelectric amorphous-oxide (glass) alkali-ion electrolytes of composition A₂.₉₉Ba₀.₀₀₅ClO (A = Li, Na) are shown by two different types of measurement and different consistent analyses to have extraordinarily high dielectric constants, varying from 10⁹ at 25 °C to 10¹⁰ ...

... Single-particle plasmon spectroscopy has become a standard technique to detect and quantify the presence of unlabeled macromolecules. Here, we extend this method to determine their exact distance from the plasmon sensors with sub-nanometer resolution by systematically varying the sensing range into the surrounding by adjusting the size of the plasmonic nanoparticles. We improved current single-par ...

... Aromatic donor–acceptor interactions are of high importance in supramolecular chemistry, materials science and biology. Compared to other noncovalent interactions, such as hydrogen bonding, the binding is often weak. Here we show that strong donor–acceptor interactions between planar aromatics with binding free energies down to −10.1 kcal mol–¹ and association constants of up to 2.34 × 10⁷ L mol–¹ ...

... We report a stereoretentive cross-coupling reaction of configurationally stable nucleophiles with disulfide and N-sulfenylsuccinimide donors promoted by Cu(I). We demonstrate the utility of this method in the synthesis of thioglycosides derived from simple alkyl and aryl thiols, thioglycosides, and in the glycodiversification of cysteine residues in peptides. These reactions operate well with carb ...

... Thermoelectric generators can convert heat directly into usable electric power but suffer from low efficiencies and high costs, which have hindered wide-scale applications. Accordingly, an important goal in the field of thermoelectricity is to develop new high performance materials that are composed of more earth-abundant elements. The best systems for midtemperature power generation rely on heavi ...

... By a combination of electron paramagnetic resonance spectroscopy, finite-temperature ab initio simulations, and electronic structure analyses, the activation of molecular dioxygen at the interface of gold nanoparticles and titania in Au/TiO₂ catalysts is explained at the atomic scale by tracing processes down to the molecular orbital picture. Direct evidence is provided that excess electrons in Ti ...

... Intercalation-type electrodes have now been commonly employed in today’s batteries as such materials are capable of storing and releasing lithium reversibly via topotactic transformation, conducive to small structural change, but they have limited interstitial sites to hold Li. In contrast, conversion electrodes feature high Li-storage capacity, but often undergo large structural change during (de ...

... For the first time, actinide endohedral metallofullerenes (EMFs) with non-isolated-pentagon-rule (non-IPR) carbon cages, U@C₈₀, Th@C₈₀, and U@C₇₆, have been successfully synthesized and fully characterized by mass spectrometry, single crystal X-ray diffractometry, UV–vis–NIR and Raman spectroscopy, and cyclic voltammetry. Crystallographic analysis revealed that the U@C₈₀ and Th@C₈₀ share the same ...

... Self-assembled 1D block copolymer nanoparticles (micelles) are of interest for a range of applications. However, morphologically pure samples are often challenging to access, and precise dimensional control is not possible. Moreover, the development of synthetic protocols that operate on a commercially viable scale has been a major challenge. Herein, we describe the preparation 1D fiber-like micel ...

... Inspired by natural biomolecular machines, synthetic molecular-level machines have been proven to perform well-defined mechanical tasks and measurable work. To mimic the function of channel proteins, we herein report the development of a synthetic molecular shuttle, [2]rotaxane 3, as a unimolecular vehicle that can be inserted into lipid bilayers to perform passive ion transport through its stocha ...

... The discovery and optimization of biomolecules that reliably function in metazoan cells is imperative for both the study of basic biology and the treatment of disease. We describe the development, characterization, and proof-of-concept application of a platform for directed evolution of diverse biomolecules of interest (BOIs) directly in human cells. The platform relies on a custom-designed adenov ...

... The functionalization of unactivated C(sp³)–H bonds of aliphatic amines catalyzed by transition-metal complexes is important because amine-based functionality is present in a majority of biologically active molecules and commercial pharmaceuticals. However, such reactions are underdeveloped and challenging to achieve in general because the basicity and reducing properties of alkylamines tends to i ...

... Two-dimensional (2D) metal dichalcogenides (MX₂) are the most common type of 2D semiconductors and have shown great potential for a wide range of chemical and physical applications. However, they are limited by a low electron/hole mobility, which has been recognized as one of the major challenges impeding their further developments, and urges efforts to understand the mobility-limiting factors and ...

... A new approach of finely tuning multinuclear clusters of metal–organic frameworks (MOFs) through symmetry-upgradingly isoreticular transformation was first presented and a bcu-type MOF, {[Cu₄(μ₄-O)Cl₂(IN)₄][CuCl₂]}∞ (NJU-Bai35; NJU-Bai for Nanjing University Bai group), with cluster [Cu₄(μ₄-O)Cl₂(COO)₄N₄] of higher symmetry compared to the pristine MOF, was successfully synthesized. The symmetry u ...